1. Field of the Invention
The present invention relates to an information recording medium, such as a high-density optical disc, on which various information can be recorded at high density, such as main picture information, audio information, sub picture information, reproduction control information, an apparatus for and a method of recording the information onto the information recording medium, an apparatus for and a method of reproducing the information from the information recording medium, an apparatus and a method capable of both recording and reproducing the information, a program storage device and a computer data signal embodiment in a carrier wave for controlling the record and the reproduction, and a data structure including a control signal for controlling the reproduction.
2. Description of the Related Art
A DVD is generalized as an optical disc on which various information is recorded, such as the main picture information, the audio information, the sub picture information, and the reproduction control information. According to the DVD standard, the main picture information (e.g. video data), the audio information (e.g. audio data), and the sub picture information (e.g. sub picture data) are individually packetized with the reproduction control information (e.g. navigation data) and are multiplexed and recorded on a disc in the “program stream” format of the MPEG 2 (Moving Picture Experts Group phase 2) standard, which is a highly efficient encoding technique. Among them, in the main picture information, there is data compressed according to the MPEG video format (ISO 13818-2), only by one stream within one program stream. On the other hand, the audio information is recorded in a plurality of methods (namely, linear PCM, AC-3, MPEG audio, and the like). The audio information can exist up to 8 streams within one program stream. The sub picture information is defined with a bit map and is compressed and recorded in a run-length method. The sub picture information can exist up to 32 streams within one program stream. In the case of the DVD, as described above, a plurality of streams of the chooseable or selectable audio information (e.g. streams of a stereo sound, a surrounding sound, an original English sound, a dubbed Japanese sound, and the like) and a plurality of streams of the chooseable or selectable sub picture information (e.g. streams of Japanese subtitle, English subtitle, and the like) are multiplexed and recorded by using the program stream format, for one stream of the main picture information in one movie (i.e. one film), for example.
On the other hand, the “transport stream” format of the MPEG 2 standard has been recently standardized, and this is appropriate for data transmission. According to this transport stream format, a plurality of “elementary streams” are transmitted at the same time. For example, a plurality of shows or programs, such as many TV channels of satellite digital broadcasting, are multiplexed in time sharing (i.e., time-division-multiplexed) to one satellite wave and are transmitted at the same time. Namely, in the transport stream format, it is possible to multiplex in time sharing the elementary streams of a plurality of main pictures, each of which has a large data amount, and transmit them at the same time. For example, it is possible to transmit at the same time a plurality of movies recorded on a plurality of DVDs.
In the above described DVD, the main picture of one stream can be multiple-recorded with the audio information, the sub picture information, and the like of a plurality of streams. However, the main pictures of the plurality of streams cannot be multiple-recorded. Namely, the DVD, with respect to which recording is performed on the basis of the program stream format of the MPEG 2, has such a problem that a plurality of shows or programs cannot be essentially recorded thereon, which are transmitted at that same time in the transport stream format of the MPEG 2 as described above.
Moreover, even if there is a disc, which has such a high transmission rate and has such a high recording capacity or such a high recording density as to be capable of recording at the same time the plurality of shows or programs transmitted in the transport stream format, it is extremely important to try to save the recording capacity on the disc and reduce the processing load at the time of the reproduction. Especially, in the reproduction of the disc of this kind, there is such a strong request as to accurately perform an interactive reproduction unique to an information reproducing apparatus or a special reproduction processing, such as searching and scanning, which is different from the case of a tuner that performs a simple tuning. It is technically difficult to try, while responding to the above request, to save the recording capacity on the disc and reduce the processing load at the time of the reproduction, which is a problem.